Shingrix would be the only other treatment for shingles approved in the US.
Shingles occurs when the varicella-zoster virus, which causes chickenpox, is reactivated, resulting in the formation of a painful, often debilitating blistering rash. It appears most often as a single stripe of blisters that wraps around either the left or the right side of the torso. The varicella-zoster virus remains latent in people once they have recovered from chickenpox. It is believed that weakening of the immune system due to stress, illness, injury, aging or the use of certain medicines can lead to reactivation. Most people recover and typically only get shingles once.
Currently, there is only one marketed shingles prevention vaccine in the US – Zostavax from Merck & Co. Zostavax was approved in 2006 and is expected to generate sales of approximately $730 million in 2017. However, if FDA follows the recommendation of its advisory panel regarding the GlaxoSmithKline’s Shingrix shingles vaccine, this could impact the current landscape. The panel voted 11-0 that the safety and efficacy of Shingrix warrants approval for its use in adults aged 50 and over.
The FDA is not required to follow the recommendations of its advisory panels, but usually does. In this case, panel members were very positive about Shirngrix, noting that they were “very impressed” by the efficacy data from clinical trials and that the new vaccine appears to be an improvement over Zostavax.
Compared to Zostavax, Shingrix was shown in clinical trials to retain greater efficacy over time. Specifically, four years after injection in trial participants over 70, Shingrix remained approximately 90% effective, while the efficacy of Zostavax declines over time. In addition, in two Phase III studies, it was found that the side effects for Shringix were similar to those observed with a placebo.
Noted Thomas Breuer, Chief Medical Officer of GSK Vaccines: “This is a new generation of vaccine, which really has overcome the age-related decline in immunity.
The new GSK vaccine, which is given in two doses two months apart, also reduces incidence of nerve pain following a shingles outbreak known as postherpetic neuralgia. Annual sales for Shingrix are forecasted to reach $1 billion by 2023, according to Thomson Reuters data. Agenus Inc., which supplies GSK a key component of the vaccine used to boost its efficacy, will receive royalties on future sales. The vaccine is also under review by regulatory authorizes in Europe, Japan, Australia and Canada.